Johnson, D. W., & Johnson, F. P. (1982). Joining together: Group theory and group skills (2nd.ed.). Prentice-Hall.
Cita Chicago (17th ed.)Johnson, David W., i Frank P. Johnson. Joining Together: Group Theory and Group Skills. 2nd.ed. New Jersey: Prentice-Hall, 1982.
Cita MLA (9th ed.)Johnson, David W., i Frank P. Johnson. Joining Together: Group Theory and Group Skills. 2nd.ed. Prentice-Hall, 1982.
Atenció: Aquestes cites poden no estar 100% correctes.